Log Follow v1.5.5
lets you see the content of text files in soft real-time. It is a
gui that gives the functionality of tail
-f while adding some extra
features. If you have never used tail -f,
the way log_follow
works is by telling it which text file you want to follow. As
another program makes changes to the log file, log_follow's main window will be
updated to stay in sync.
log_follow has some extra
features that are difficult to script using tail -f. If you look at the
screen capture above, you will see three checkboxes. The first
checkbox is labeled "Scroll." If enabled, log_follow will automatically
scroll when new text is added; if disabled, log_follow will not scroll.
By disabling scroll, it will be much easier to keep your place while
reading. As a convenience, any time you click in the window,
e.g., to copy text, scroll will be disabled. You can
automatically start log_follow
in scroll mode by adding the -s command-line flag.
The second checkbox is labeled "Warp." When warp is enabled, log_follow will automatically
switch to view any new log file that is detected. log_follow considers a new log file
to be any file with the same basename as the file you are currently
following. For example, if you are viewing the file log.001 and log.002 is created in the same
directory, log_follow will
stop viewing log.001 and
start viewing log.002.
You can automatically start log_follow
in warp mode by adding the -w command-line flag.
The third checkbox is labeled "Incoming." This checkbox is used
to alert you when something new has been logged. If you specify
the "--odelay <secs>" option, the checkbox will automatically
uncheck itself after <sec> seconds delay. With or without
the --odelay flag, log_follow
will respect your manual control of the checkbox which allows you to
manually mark all text as old at any time.
log_follow knows how to color
text to make it easy to distinguish new text from old text. Just
add the "--nfg <color>" and the "--ofg <color>"
command-line flags to set the new and old foreground colors
respectively. You can also add the "--blink" command-line flag to
force log_follow to flash a
visible bell when something new is logged. Lastly, you can use
the "--cr" flag to instruct log_follow
to allow you to use <enter> to input carriage returns at the
cursor or <ctrl><enter> to insert a
carriage returns at the end of file. The
extra spacing can be used to help you visually separate parts of the
log file. (The carriage returns are not written to disk.)
For this release, log_follow
detects changes by polling. The default is
to check about every half second. If you want more responsiveness or
less cpu consumption, you can alter the polling periods. Use the
"--pc <freq>" command-line flag to alter how frequently you check
for new content. Use the "--pf <freq>" command-line
flag to alter how frequently you check for new log files.
You can jump to the bottom of the file using
<ctrl><arrow_down> and return using
<ctrl><arrow_up>. This allows you to
bookmark what you are currently reading so you can see new log messages
without losing your place.
The log file you want to follow does not have to be in existence
when you start log_follow.
For example, if you start log_follow
with "log_follow -s -w log" when no "log.*" files are present, log_follow will detect when they
are created and load them then.
You can see all the command-line flags by starting log_follow with the -h flag.
program creates log files that are periodically
truncated when the log files are rotated by cron. You can follow this
type of log file by starting log_follow
Some operating systems make it hard to write to stdout or stderr.
On these systems, you can create your own log file and use log_follow
to view its contents as
program creates a new log file for each game played. crafty
's log files are named log.001
, etc. You can follow
's log files by starting
-s -w log
The command I use for starting crafty
is as follows:
--blink --cr -s -w -nfg blue -odelay 10.0 log
can color code its
so you can easily distinguish between new and old text. (Not all color
combinations are possible. So, don't waste too much time if your
command-line options are overridden with black or white.) The command
used for starting the instance of log_follow
in the screen capture above is
-s --cr --bg black
-nfg yellow -ofg cyan
I provide pre-built executables. To
run, just download the correct executable below for your system.
Place it in any
directory and make sure the file permissions on your copy allow
The source is not currently
downloadable because log_follow
uses some unrelated
personal libraries that are not part of the source tree proper.
anyone is interested in the source, I might make the
time to merge these libraries with the log_follow
code to make one
coherent source tree. If you want to build a program from source
to follow crafty
's log files,
- Windows Executable for
XP, and successors. It will not work with Win95, Win98, WinME,
Log Follow is released under a